NCQ-Aware I/O Scheduling for Conventional Solid State Drives

Abstract : While current fairness-driven I/O schedulers are successful in allocating equal time/resource share to concurrent workloads, they ignore the I/O request queueing or reordering in storage device layer, such as Native Command Queueing (NCQ). As a result, requests of different workloads cannot have an equal chance to enter NCQ (NCQ conflict) and fairness is violated. We address this issue by providing the first systematic empirical analysis on how NCQ affects I/O fairness and SSD utilization and accordingly proposing a NCQ-aware I/O scheduling scheme, NASS. The basic idea of NASS is to elaborately control the request dispatch of workloads to relieve NCQ conflict and improve NCQ utilization. NASS builds on two core components: an evaluation model to quantify important features of the workload, and a dispatch control algorithm to set the appropriate request dispatch of running workloads. We integrate NASS into four state-of-the-art I/O schedulers and evaluate its effectiveness using widely used benchmarks and real world applications. Results show that with NASS, I/O schedulers can achieve 11-23% better fairness and at the same time improve device utilization by 9-29%.
Complete list of metadatas

Cited literature [36 references]  Display  Hide  Download

https://hal.inria.fr/hal-02389113
Contributor : Shadi Ibrahim <>
Submitted on : Tuesday, December 3, 2019 - 11:27:59 AM
Last modification on : Wednesday, December 4, 2019 - 1:28:38 AM

File

NCQ-AwareIOSchedulingforConven...
Files produced by the author(s)

Identifiers

Citation

Hao Fan, Song Wu, Shadi Ibrahim, Ximing Chen, Hai Jin, et al.. NCQ-Aware I/O Scheduling for Conventional Solid State Drives. IPDPS 2019 - 33rd IEEE International Parallel & Distributed Processing Symposium, May 2019, Rio de Janeiro, Brazil. pp.523-532, ⟨10.1109/IPDPS.2019.00062⟩. ⟨hal-02389113⟩

Share

Metrics

Record views

34

Files downloads

82